Cita APA (7th ed.)

WILLIAMS, E., & SHUARD, H. (1970). Elementary mathematics today: A resource for teachersgrades 1-8. Addison-Wesley Pub. Co.

Cita Chicago (17th ed.)

WILLIAMS, Elizabeth, i Hilary SHUARD. Elementary Mathematics Today: A Resource for Teachersgrades 1-8. Menlo Park: Addison-Wesley Pub. Co, 1970.

Cita MLA (9th ed.)

WILLIAMS, Elizabeth, i Hilary SHUARD. Elementary Mathematics Today: A Resource for Teachersgrades 1-8. Addison-Wesley Pub. Co, 1970.